Create a discourse cookbook that can be wrapped

It makes it possible to serve multiple Discord instances to different
hosts from a single nginx load balancer

Right now we run one for Kosmos and one for remoteStorage

site-cookbooks/discourse/templates/nginx_conf.erb

@@ -0,0 +1,36 @@
+# Generated by Chef
+upstream _<%= @upstream_name %> {
+  <% @upstream_ip_addresses.each do |upstream_ip_address| -%>
+  server   <%= upstream_ip_address %>:<%= @upstream_port %>;
+  <% end -%>
+}
+
+<% if File.exist?(@ssl_cert) && File.exist?(@ssl_key) -%>
+server {
+  server_name <%= @server_name %>;
+  listen 443 ssl http2;
+  listen [::]:443 ssl http2;
+
+  ssl_certificate     <%= @ssl_cert %>;
+  ssl_certificate_key <%= @ssl_key %>;
+
+  add_header Strict-Transport-Security "max-age=31536000";
+
+  # Send real IP to the Docker container
+  set_real_ip_from 127.0.0.1;
+  real_ip_header X-Forwarded-For;
+
+  client_max_body_size 20M;
+
+  location / {
+    # Increase number of buffers. Default is 8
+    proxy_buffers 1024 8k;
+
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto https;
+
+    proxy_pass http://_<%= @upstream_name %>;
+    proxy_http_version 1.1;
+  }
+}
+<% end -%>